1. Field
The present invention generally relates to techniques for monitoring computer systems. More specifically, the present invention relates to a method and an apparatus that estimates a power utilization of a computer system.
2. Related Art
The power needs of computer data centers are typically estimated by adding up the maximum power usage rating for each computer system to be installed in the center. This may substantially overestimate the power requirements for the data center, resulting in increased costs in setting up the center. Data center operators desire a more accurate estimate of the actual power used by computer systems during operation of their data centers in order to better match the power provisioning of their center to the actual needs. Power monitoring is also useful in a hosting/co-location datacenter, where a customer of the hosting company is billed on the power used by the server rather than a flat rate per month, or in a multi-business datacenter where each business unit is billed for the exact amount of power they use.
In order to directly measure the power used by a computer system, hardware power meters could be installed, but this may not only be costly but also could require computers to be powered down for installation. Other techniques for determining the power utilized by a computer system involve measuring parameters of the computer during operation and inferring the power utilization, or using a power utilization lookup table based on the operating parameters of the computer system. However, many current computer systems have a dynamic power-management feature that can vary the power consumption of the computer system by changing, for example, the operating frequency and voltage of the processor, allowing the computer system to operate in a large number of operating modes with varying power consumption levels. Some computers also have chipsets that power-down unused PCI and USB controllers. With FBDIMMs there is the capability to throttle the memory, which reduces heat and power usage. Therefore, inferring the power utilization of a computer system based on generating a model from each allowable state or generating a power lookup table that includes all operating states of the computer system is an undesirable solution for computer systems that can implement dynamic power management.
Hence, what is needed is a method and system that estimates a power utilization of a computer system without the above-described problems.